Tumor cell-intrinsic programmed death-ligand 1 (PD-L1) signals mediate tumor initiation, progression and metastasis, but their effects in ameloblastoma (AM) have not been reported. In this comprehensive study, we observed marked upregulation of PD-L1 in AM tissues and revealed the robust correlation between elevated PD-L1 expression and increased tumor growth and recurrence rates. Notably, we found that PD-L1 overexpression markedly increased self-renewal capacity and promoted tumorigenic processes and invasion in hTERT⁺-AM cells, whereas genetic ablation of PD-L1 exerted opposing inhibitory effects. By performing high-resolution single-cell profiling and thorough immunohistochemical analyses in AM patients, we delineated the intricate cellular landscape and elucidated the mechanisms underlying the aggressive phenotype and unfavorable prognosis of these tumors. Our findings revealed that hTERT⁺-AM cells with upregulated PD-L1 expression exhibit increased proliferative potential and stem-like attributes and undergo partial epithelial‒mesenchymal transition. This phenotypic shift is induced by the activation of the PI3K-AKT-mTOR signaling axis; thus, this study revealed a crucial regulatory mechanism that fuels tumor growth and recurrence. Importantly, targeted inhibition of the PD-L1-PI3K-AKT-mTOR signaling axis significantly suppressed the growth of AM patient-derived tumor organoids, highlighting the potential of PD-L1 blockade as a promising therapeutic approach for AM.
Ameloblastoma/metabolism* ; Humans ; B7-H1 Antigen/metabolism* ; Neoplasm Recurrence, Local/pathology* ; Signal Transduction ; Cell Proliferation ; Up-Regulation ; TOR Serine-Threonine Kinases/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Telomerase/metabolism* ; Jaw Neoplasms/metabolism* ; Epithelial-Mesenchymal Transition ; Animals ; Cell Line, Tumor ; Female ; Male

OBJECTIVE: To investigate the effectiveness of posterior lateral perforator flap in lower limb combined with free fibula for maxillary tissue defect repair. METHODS: Between December 2018 and December 2023, 16 patients with the maxillary malignant tumors were admitted. There were 10 males and 6 females, with an average age of 64.3 years (range, 54-75 years). There were 7 cases of maxillary gingival cancer, 5 cases of hard palate cancer, and 4 cases of maxillary sinus cancer. According to the 2017 American Joint Committee on Cancer (AJCC) TNM stage, there were 8 cases of stage Ⅲ, 6 cases of stage Ⅳa, and 2 cases of stage Ⅳb. After resection of the lesion, the remaining maxillary defects were classified into class Ⅱa in 3 cases, class Ⅱb in 5 cases, and class Ⅲb in 8 cases according to Brown's classification. The size of soft tissue defects ranged from 4 cm×3 cm to 8 cm×6 cm. The posterior lateral perforator flap in lower limb in size of 5 cm×4 cm-9 cm×7 cm were harvested to repair soft tissue defects, and free fibula in length of 6-11 cm were used to repair bone defects. The donor sites of the lower limb were sutured directly (6 cases) or repaired with free skin grafting (10 cases). Six patients with positive lymph node pathology were treated with radiotherapy after operation. At 6 and 12 months after operation, the self-assessment was performed by the University of Washington Quality of Survival Questionnaire Form (QUW-4) in five dimensions (facial appearance, swallowing function, chewing function, speech function, and mouth opening), and swallowing function was evaluated by using the Kubota water swallowing test. RESULTS: Postoperative pathological examination showed that all patients were squamous cell carcinoma. One patient who was treated with radiotherapy developed osteomyelitis and 1 patient developed venous crisis of skin flap. The rest of the flaps and all skin grafts survived, and the wounds healed by first intention. All patients were followed up 1-5 years (mean, 2.8 years). Two patients died of local recurrence of the tumor at the 4th and 5th years after operation, respectively. Except for the chewing function score and total score at 6 months after operation, which showed significant differences compared to preoperative scores ( P<0.05), there was no significant difference in other QUW-4 scale scores between different time points ( P>0.05). The patients' swallowing function evaluated by Kubota water swallowing test reached normal in 4 cases, suspicious in 9 cases, and abnormal in 3 cases at 6 months after operation, and 10, 6, and 0 cases at 12 months after operation, respectively. The swallowing function at 12 months was significantly better than that at 6 months ( Z=-2.382, P=0.017). CONCLUSION The posterior lateral perforator flap in the lower limb combined with free fibula to repair maxillary tissue defects can repair soft and hard tissue defects at the same time, so that the patient's facial appearance, swallowing function, chewing function, speech function, and mouth opening are satisfactorily restored and the mid-term effectiveness is good.
Humans ; Middle Aged ; Male ; Female ; Fibula/surgery* ; Aged ; Perforator Flap ; Plastic Surgery Procedures/methods* ; Maxilla/surgery* ; Maxillary Neoplasms/surgery* ; Free Tissue Flaps/transplantation* ; Lower Extremity/surgery* ; Bone Transplantation/methods* ; Treatment Outcome

OBJECTIVES: To investigate the clinical application of the digital-assisted reconstruction of the mandible and tumors with free fibula transplantation and immediate implantation via the intraoral approach. METHODS: Twelve patients with benign mandibular tumors were collected. Three-dimensional mandibular reconstruction was performed digitally before surgery to simulate mandibular tumor resection, fibula resection and reconstruction, and implant implantation. The intraoperative resection of the mandibular tumor was conducted through the intraoral approach under the guidance of a guide plate, and fibula resection, molding, reconstruction, and oral fixation were immediately performed. Implant implantation was performed during the second phase of implant surgery and denture restoration was performed 1-2 months after surgery. RESULTS: The types of mandibular defects were BrownⅠ (one case), Ⅰc (four cases), Ⅱ (one case), Ⅱc(three cases), and Ⅲ (three cases). The length of the fibular bone was 12-22 cm. The number of fibular molding amputations was as follows: two cases in two segments, six cases in three segments, three cases in four segments, and one case in five segments. All of these cases underwent folding fibular reconstruction of mandibular and alveolar bone defects. A total of 44 implants were implanted, and none failed after operation. CONCLUSIONS The intraoral approach is a reliable method for the resection of mandibular benign tumors, with few postoperative complications and the ability to position and fix accurately the reconstructed folded fibula under digital design. The immediate implantation of the transplanted fibula does not affect the blood supply and has a high success rate. It is an effective and reliable method for the resection and reconstruction of mandibular benign tumors.
Humans ; Fibula/transplantation* ; Mandibular Neoplasms/surgery* ; Mandibular Reconstruction/methods* ; Bone Transplantation/methods* ; Male ; Middle Aged ; Female ; Mandible/surgery* ; Adult ; Free Tissue Flaps ; Surgery, Computer-Assisted

Adenoid cystic carcinoma is a malignant tumor of the head and neck, this article reports a case of a large adenoid cystic carcinoma of the skull base, with the lesion involving the sphenoid sinus, sphenoid bone wings, pterygopalatine fossa, nfratemporal fossa, hard palate, and other structures. The treatment plan consisted of surgical excision, primary reconstrction of the surgical defect,and postoperative radiotherapy, resulting in a favorable prognosis for the patient.
Humans ; Carcinoma, Adenoid Cystic/surgery* ; Maxillary Sinus/surgery* ; Maxillary Sinus Neoplasms/surgery* ; Palate, Hard/surgery* ; Skull Base Neoplasms/surgery* ; Surgical Flaps

Objective:To investigate the clinical effect of free anterolateral thigh myocutaneous flap combined with oral repair membrane in the reconstruction of nasal mucosa defect after maxillary malignant tumor surgery. Methods:A total of 12 patients with maxillary gingival squamous cell carcinoma and maxillary sinus cancer who had been treated in Department of Oral and Maxillofacial Surgery, Beijing Anzhen Nanchong Hospital, Capital Medical University & Nanchong Central Hospital, were selected from November 2020 to November 2023. Free anterolateral thigh musculocutaneous flap transplantation combined with oral repair membrane were used in all patients. Meanwhile, maxillary soft and hard tissue defects and nasal mucosa defects left after tumor operation were repaired and reconstructed. The clinical effect was evaluated after 6-12 months follow-up. Results:Subtotal maxillary resection was performed in 1 case, total maxillary resection in 9 cases and extended maxillary resection in 2 cases. The musculocutaneous flaps of all patients survived, the facial appearance was basically symmetrical, no obvious depression deformity, the swallowing and speech function recovered well, the mouth and nasal cavity were closed completely, the food could be eaten through the mouth, and the lower nasal passage was not blocked. Conclusion:The free anterolateral thigh musculoflap combined with oral repair membrane can be used to repair and reconstruct maxillary malignant tumor complicated with extensive maxillary tissue and nasal mucosa defect after operation, and the appearance and function can be recovered well after operation, which is a choice for maxillary malignant tumor complicated with nasal mucosa defect.
Humans ; Myocutaneous Flap ; Plastic Surgery Procedures/methods* ; Maxillary Neoplasms/surgery* ; Carcinoma, Squamous Cell/surgery* ; Male ; Middle Aged ; Female ; Nasal Mucosa/surgery* ; Maxilla/surgery* ; Thigh/surgery* ; Maxillary Sinus Neoplasms/surgery*

OBJECTIVE

To determine if the prelacrimal window approach is feasible in a Filipino population by measuring the distance between the anterior maxillary wall and lacrimal duct in paranasal sinus CT scans, classifying them into prelacrimal window approach levels of difficulty.

Design: Retrospective Review of Records

Setting: Tertiary Private University Hospital

Participants: PNS CT scans of Filipino patients 18 years old or above

A total of 169 PNS CT scans were reviewed, measuring the right and left sides for a total of 338 sides. The mean prelacrimal window distance for males was 5.70mm (±1.79), while for females it was 4.94 (±1.75), with a combined mean distance of 5.32mm. Ten percent (10%) of CT scans (34) were classified as Type 1; 73.7% (249) were classified as Type 2, and 16.3% (55) were classified as Type 3.

The prelacrimal window approach may be anatomically feasible in the Filipino population studied, with 90% of the PNS CT scan sides reviewed falling into the Type 2; and Type 3 categories, opening more potential avenues in the management of anterior maxillary lesions in the Philippines.

Fibro-osseous lesions is a class of diseases with obvious similarities in clinical manifestations and pathological features, which has been attracting the attention of clinicians and pathologists. The latest WHO 2022 Classification (5th edition) included six of these diseases (cemento-osseous dysplasia, segmental odontomaxillary dysplasia, fibrous dysplasia, juvenile trabecular ossifying fibroma, psammomatoid ossifying fibroma and familial gigantiform cementoma) in the " fibro-osseous tumours and dysplasias ", and put forward new ideas on the diagnosis and treatment of these diseases. According to the latest WHO 2022 Classification (5th edition), the clinical and pathological features, diagnosis and differential diagnosis of these six diseases were described.
Humans ; Fibroma, Ossifying/pathology* ; Diagnosis, Differential ; Cementoma/pathology* ; Jaw Neoplasms ; Facial Bones

At present, mandibular defect repair and reconstruction is not only a simple sense of mandibular continuity restoration, but also a restoration of the physiologically positional relationship and movement balance of the upper and lower jaws. Eventually, the implantation of osseointegrated dental implants and implant-supported dental restoration should be accomplished to complete the reconstruction of the functional mandible. The technique can integrate multiple procedures such as fibular bone grafting, simultaneous dental implants and traction osteogenesis, and the perfect integration with digital technology can significantly improve the accuracy of digital dental implant traction technique. This paper will summarize and conclude the key points of the application of digital dental implant traction technique in mandibular defect reconstruction, in order to provide new ideas for the development of digital technique.
Humans ; Mandibular Reconstruction ; Dental Implants ; Dental Implantation, Endosseous/methods* ; Mandibular Neoplasms/surgery* ; Fibula/transplantation* ; Bone Transplantation/methods* ; Mandible/surgery*

Medication-related osteonecrosis of the jaw (MRONJ) is a serious adverse event related to administration of antiresorptive or antiangiogenic medications. With the increasing usage of bone-modifying agents in cancer therapy, the incidence of MRONJ enhanced gradually, which affects the life quality of patients and interferes with cancer therapy. In 2019, Multinational Association of Supportive Care in Cancer (MASCC), International Society of Oral Oncology (ISOO) and American Society of Clinical Oncology (ASCO) convened a multidisciplinary Expert Panel to evaluate the evidence and formulate recommendations on practices in the prevention and management of MRONJ in patients with cancer. The present article made an interpretation of Medication-Related Osteonecrosis of the Jaw: MASCC/ISOO/ASCO Clinical Practice Guideline so as to provide clinicians with diagnostic and therapeutic approaches for cancer patients with MRONJ.
Bisphosphonate-Associated Osteonecrosis of the Jaw/therapy* ; Bone Density Conservation Agents/adverse effects* ; Humans ; Jaw ; Medical Oncology ; Neoplasms/drug therapy* ; Osteonecrosis/chemically induced* ; Quality of Life

Objective: To analyse the quality of life of patients receiving repair of bone defect with folded fibula flap after removal of mandibular ameloblastoma. Methods: The case data of 39 patients with ameloblastoma admitted to the First Affiliated Hospital of Zhengzhou University from August 2013 to April 2016 were retrospectively analysed, including 21 males and 18 females, from 18 to 58 years old. 3D printing and digital technology were used in flap preparation before surgery in all patients. The folded fibular flaps were used to repair mandibular defects and the implants were placed between 6-9 months after surgery. The short form-36 health survey questionnaire (SF-36) and the university of Washington quality of life questionnaire (UW-QOL) were applied to evaluate the quality of life of patients before surgery and at 6 months and 24 months after surgery. The higher the score, the better the condition. SPSS 20.0 was adopted for statistical analysis. Results: The SF-36 survey showed that the mean score of body role before surgery (72.4±11.7) was significantly higher than that at 6 months after surgery (39.6±11.1, t=23.580, P<0.05) or that at 24 months after surgery (59.8±6.4, t=8.358, P<0.001). Compared with the preoperative mean scores of Physical Pain (73.0±11.0), General Health (73.4±10.4) and Health Changes (79.2±3.9) before surgery, the mean scores Physical Pain (53.1±7.7), General Health (53.5±7.5) and Health Changes (63.9±11.7) at 6 months after surgery were decreased significantly respectively (t=13.068, 13.756 and 10.880, respectively, all P<0.05), but the mean scores Physical Pain (78.8±14.0), General Health (80.9±12.6) and Health Changes (84.4±4.6) at 24 months after surgery were increased significantly respectively (t=-2.904, -4.027 and -7.586, respectively, all P<0.05), with significant differences in the mean scores of Physical Pain, General Health and Health Changes between 6 and 24 months after surgery (t=-14.241, -16.490, -14.294, respectively, all P<0.001). The UW-QOL survey showed that the mean scores of chewing, language and taste functions decreased at 6 months after surgery (53.1±6.7, 53.0±7.7 and 62.2±9.9, respectively), but improved at 24 months after surgery (67.9±3.9, 63.9±2.9 and 68.4±11.1, respectively), with statistically significant difference (t=-16.765, -11.675 and 2.498, respectively, all P<0.001). Conclusion: The application of folded fibula flaps to repair bone defects after sugery of mandibular ameloblastoma can better meet the needs of language and chewing functions and improve the quality of life of patients.
Adolescent ; Adult ; Ameloblastoma/surgery* ; Bone Transplantation ; Female ; Fibula/surgery* ; Free Tissue Flaps ; Humans ; Male ; Mandible/surgery* ; Mandibular Neoplasms/surgery* ; Middle Aged ; Quality of Life ; Reconstructive Surgical Procedures ; Retrospective Studies ; Young Adult